Dehydration is a frequent cause of morbidity and mortality in the elderly. Identifying at risk individuals and maintaining adequate fluid balance is an essential component of health care in the aging population. Currently, there is no effective tool available to measure hydration status and distinguish those at risk. The reliability and validity of current hydration assessment methods and criteria such as thirst, skin turgor, blood pressure, pulse, urine output and specific gravity, MRI, dilution methods and bioimpedance, are limited, and the methods are inaccurate or expensive. Given that dehydration is both preventable and reversible, the need for an easy- to-perform method for the detection of water imbalance is of the utmost clinical importance. The goal of this project is to develop an inexpensive and easy-to-use device that monitors changes in hydration status and predict those at risk in home-bound and institutionalized elderly. We propose to develop the Hydration Monitor (HM) that can objectively quantify changes in the body water content and hydration status. The method implemented in the device is based on the experimental fact that ultrasound velocity through soft tissue is a linear function of the tissue water content. Because muscle provides the largest body reservoir for water, the assessment of water imbalance is conducted by measuring speed of ultrasound in muscle. Preliminary studies confirmed feasibility of Hydration Monitor, a compact hand-held device based on a proprietary ultrasonic technology developed in Artann Laboratories. The aims of this Phase I SBIR project include (1) designing and manufacturing of HM prototype, which will be tested for its ability of measuring ultrasound velocity in water as test medium with accuracy better than 1 m/s; (b) testing and validating HM prototype on tissue phantoms and excised animal tissues, demonstrating the sensitivity to water content changes should be better than 2%; and (3) designing the HM -prototype and preparing documentation for building the HM -prototype in Phase II of the project for clinical studies. PUBLIC HEALTH RELEVANCE: Currently, there is no effective tool available to measure body dehydration, which is a frequent cause of morbidity and mortality in the elderly. We propose to develop a compact hand-held Hydration Monitor that can objectively quantify changes in the body water content and assess hydration status. The device is based on a proprietary patented ultrasonic technology developed in Artann Laboratories.